Probably greatness is most powerful if there are enough powerful mediocrities to work against.
Bismarck? Or >his liberal father Might be a stretch to imply that the Wilhelm II was a mediocre illiberal. HIM was (for a time) interested in protecting workers' rights. However great he was, Bismarck couldn't overpower a "mediocre" populist https://germanhistorydocs.org/en/forging-an-empire-bismarcki...
Assume every side has great individuals in positions of power (great being here evidently in relation to ability), greatness is thus evenly balanced and not so important to the final outcome.